Electrical impulse sending device



Jan. 27, 1948. G. DEAKIN 2,434,910

ELECTRICAL IMPULSE SENDING DEVICE V Original Filed Feb. 24, 1944 2 SheetsSheet l AGENT Jan. 27, ,1948. G. DEAKlN ELECTRICAL IMPULSE SENDING DEVICE Original Filed Feb. 24, 1944 2 Sheets-Sheet 2 m m m w.

AG'EN T Patented Jan. 27, 1948 UNITED STATES PATENT OFFlCE' ELECTRICAL IIVIPULSE SENDING DEVICE Gerald Deakin, New York, N. Y., assfgnor to International Standard Electric Corporation, New York, N. Y., a corporation of Delaware Original application February 24, 1944, Serial No. 523,626, now Patent No. 2,406,001, dated August 20, 1946. Divided and this application March 19, 1945, Serial No. 583,478

cation switching systems such as automatic and semi-automatic telephone exchanges.

An object of the invention is to increase the speed and reliability with which control impulses may be transmitted from a first point to a second point, for example, from a substation or the like to a control exchange or other position where selecting equipment is located.

With this object in view, I have provided in my copendinq applica ion No. 523,626, filed February 24, 1944, now U. S. Patent No. 2,406,001, granted August 20, 1946, of which this application is a division an arrangement in which upon the extension of a line to a distant point at which a selective control is to be exercised, a source of alternating current is coupled to the line. A signalling device, such as a dial, is then actuated to periodically reverse the polarity of a uni-directional current conducting device, such as a dry contact rect fier, in the line circuit. At the distant point there is connected to the line circuit polarized relay means which responds to the reversals of polarity of the current flow and contros switching apparatus thereat.

The pulse cycle of the standard interrupter dial circuit at present used in automatic telephone exchange systems consists of a closure and an opening of a. single stepping relay direct current circuit with a 60/40 rat o of opening to clo-- sure. One digit is recorded per cycle, and the opening of the circuit is the useful part of the cycle; the closure of the circuit represents time unavo dably wasted to prepare the circuit to receive the next ulse. In alternating current rectifier dialing circuits the compete pulse cycle consists of two pulses, a positive pulse and a negative pulse ea ch one u eful in recording a-digit as well as in assisting the restorat on ,of the relay which is operated by the preceding pulse of opposite polarity. For example, in a preferred arrangement in which two o positely polarized relays are used for responding to the pulses. these two relays o erate on a "bush-up. push-b ck princip e and thus the com lete cycle is used by both re ays while rect fication with polar zation places the operation of the two relays 180 out of phase. p

The positive and ne ative pulses consist in fact of tra ns of positive and negative pulses at the periodicity of the alternating current source, but

for all practical purposes these integratedseries of pulses act as though they were pulses of the direct current of the proper polarity.

An ob ect of the present invention is the provision of a simple and efiective device for intermittently reversing the polarity of a uni-directional current conducting device in the line circult, a. predetermined and variablenumber of times. 1

These and other features and advantages of my invention will be more clearly understood from the following description of a preferred embodiment thereof and the appended claims.

In the accompanying drawings:

Fig. 1 is a circuit diagram of a subscriber set circuit provided with a rectifier dial for use in a system, as described in my copending applica Fig, 6 shows a detail of the spring nest in the rectifier dial.

' Referring first to Fig. l, the subscriber set circuit shown therein is apart from the rectifier dial of the usual type. The rectifier dial which will be described later in connection with Figs. 2 to 6 includes a rotatin rectifier R and a home contact spring nest S. The operation of the rectifier dial from a circuit point of view is as fol lows: When the fin er wheel is moved off normal 2. pin P3 allows spring B to break contact with spring C which removes ashort circuit from the rectifier R, and to make contact with s ring A which short circuits the induction coil and tr nsmitter. Pin Pl causes spring F to break contact with spring G until shortly before the first finger hole reachesthe finger stop: in other words, the line circuit is momentari y opened each time the'fin er wheel is turned to the finger stop.

When the finger wheel is released the rectifier R makes one-half of a revolution for each finger hole passing the finger stop but before the last fin er hole passes the fi ger ston Pl again opens cont ct between the sprin s IE and G thereby momentarily opening the line circuit wh ch causes turned to its predetermined-position of polarity.

3 Thus, should an odd digit be dialed the rectifier is given a half revolution to restore it to its normal position while contact between springs F and G is open,

From what hasheen. said above iitwill'be seena that when the digit 1 is dialed the initial closureof the line through the rectifier R in its normal position sends the first pulse to record the digit 1- and that when the finger wheel isreleased. the circuit is opened for the change-over before the rectifier reverses the current;

The sub-station set circuit. shown in Fig; 1

intended for use with a system incorporating reg isters of the kind shown in my-copending application referred to in whicha-direct. current loop is resent over the subscriberfs;lineuntii; dialing; actually commences. In an alternative method of operation alternating current is applied to the subscribers line as soon. as the register is connected up.

The construction of a suitable rectifier dial. is illustrated in Figs: 2' to 6 and will now be de-- scrihedi Referring firstparti'cularly to Figs; 3 and 4, the dial" consists of two-main-parts; arr upper art I-' housing the home -contact nest HO and a lower part 2 housing the rotatingrectifier'Si In the upper hou ing I is mounted a finger to engage the teeth of aratchet wheel= HI under the tension ofa spring l-fla.

Ratchet wheel I and a gear wheel I l are attached't'oeach other and rotate'f'reelv on the lower extensionofshaft li They'areheld hr positionbythe fiat head i'la' of a bearingpi'n I 2" when the lower part 2 housing the-rectifierunit is mounted imposition. Hatchetwheel II has a number of teeth corresponding to the number of positions of the no ger wheel 3. Everyot'her tooth is relatively long (in a radial sense). When the finger wheel 3- is in its normal posit 'orrone edge of the segment I rests against a back' stopl3 formed in thehousing i am? araised surface I4 on the inner periphery of the-housing I adjacent the'stop1'31ifts thepawl fl so that it engages'only" the-deepteeth ofa ratchet l0;

When the. finger wheel 3 is; rotated by-the user;

the segment 1 moves clockwise and-when it has" moved an angular distanceequaI to about one' fingerholespacing the raised surface I l no longer bears on the pawlil and the latter rotates sl ghtly about its pivot so as to" engage both the long and the short teeth of the ratchet wheel Ill. Should the finger wheel be turned a distance equal to five fingerhol'es; that is; should the'd'igitlrbe dialed; since there i's'a space equal to twofingerholes between the hole number I and the finger stop 19;

the pawl! wilT'engage-ashort toot-hf the 65 finger wheelv is released the springB-Mllrot'at'ethe ratchet wheel "ID- connterclockwise. As the -seg= ment-l approaches-its home position, the pawl 9 engages the raised surface l4 and thus d'isenga ges the short tooth but reengages the next longtooth just before the segment T comes to rest against its predetermin ed" position of polarity;

The-home springnextconsists of five springs insulating material 30 fixed to the upper housing I. Two pins PI and P3 are mounted on the se ment 1 in such position that when the finger wheel is moved off normal, pin Pl opens the contact between springs F and'G', whilstpin P3 opens the-contact between springsB and C and permits contact to be made between springs A and B. The segment I is of insulating material.

Assume. now that, the digit 1 is dialed. When the finger is placed in hole number 1, Fig. 2, and the/finger wheel: is: moved oif normal, pin Pl engagesthetio I 5 or the extension of spring F, Figs. iar-1&6; andbreaks the normal contact between springs. F and; Ge. Spring F is cut away at its lower edge and; provided with an inclined lip [6. When the hole-number 1 has been moved an angular distance: less: than two finger hole spaces, pin Pl. rides over the lip I6, Fig. 4, and disengagesthe spring F, so that when the finger reaches the finger stop l9 contact between springs F and G- is again made-,- The three home contact springs; A, B and Care shown in theirnormali positions in Fig; 4'. When segment I is movedi of? normal pin P3 disengages spring-B thereby causing contact to be broken with spring C and made with spring'A. The springs A, Band Oremain in this position untilthedial returns-to normal.

Whenthe finger wheel 3is released, after it has moved al'aout three quarters of a finger holespace; pin Plreengages the projecting lip l6 of" fier unit and brush 2% is clampedagainst the d sc on the other sideby means of nuts 22; A-

bearing' pin I 2- which passes through the bushing; 2'l has screwed toit a gear wheel-23 and rotatesin bushings 24 attached to the upper and lower covers of the rectifier housing 2; Thebearing pin I2 is grooved so that when it is slipped through the bore of'the bushing 2| the rectifier assembly S and brushes 20a and 2th rotate with the hear-- ing pin- I'Zand the gear wheel 23;

The upper and lower brushes-20a and 20h rub" against collector rings 24a and 24!) mounted onthe inside wall of the housing; 2 as shown in Fig.

5. The external connections are connected to the" collector rings 24a and 24b. G'earwheclsll and 23 are interconnected by pinions 25which are attached toeach other and held in position by a: bearing pin 26 mounted in the lower end of'the housing portion 2. The ratchet and gear wheels" are assembled so that when the wheel lB-is in the position shown in Fig. 4 therotatin grectifier'unit S is in the position shown in Fig. 5. The ratio of the various gears is such that the rectifier unitS makes one complete revolution when the finger wheel 3 moves an angular distance equal to twofinger holespaces;

The setting of brushes 20a and 20b; Fig; 5, is such that when they engage the insulating surfaces 2T between the collector rings Zia" and 23b aspositi on 2 of the ratchet wheel passes the normal position I' on the return journey; the pi'nPt engages lip !6 of the spring F and opens the contact between springs Fahd Gi Thus the contact between these springsis opened" before the-- brushes 28a and-20h make contact with theisuc' As speed control of a rectifier dial is not critical it is sufiicient to weight the brushes 20a and 2% at their ends so that they act both as governor Wings as Well as collector brushes.

Although the invention has been described with reference to a specific construction of rectifier dial my invention is not to be construed as limited to this construction since many modifications coming within the scope of the appended claims will readily occur to those versed in the art. Moreover as will be appreciated the rectifier dial of my invention is applicable for use in any type of selector system in which the operation of switching apparatus is controlled by trains of impulses.

What is claimed is:

1. A pulsing device for a telecommunication switching system, comprising a uni-directional current conducting element, a pair of contacts for connecting said element in signalling circuit, means for connecting two output electrodes of said element respectively to said contacts and means between said contacts and said element for rotating said element and said means for connecting with respect to said contacts whereby the polarity of said element with respect to said contacts is intermittently reversed a predetermined and variable number of times.

2. A pulsing device for a telecommunication switching system comprising a rectifier, contacts for connecting said rectifier in an external signalling circuit and means between said contacts and said element for rotating said rectifier with respect to said contacts whereby the direction of polarity of said rectifier with respect to said contacts is reversed a predetermined and variable number of times.

3. A pulsing device for a telecommunication switching system comprising a unidirectional current conducting element, contacts for connecting said rectifier in an external signalling circuit, a rotatable member, means for turning said rotatable member a variable angular distance, and means between said contacts and said element under the control of said rotatable member for rotating said element with respect to said contacts whereby the direction of polarity of said element is reversed with respect to said contacts a predetermined number of times dependent upon the extent of the angular movement of said rotatable member.

4. A pulsing device for a telecommunication switching system comprising a dry contact rectifier, contacts for connecting said rectifier in signalling circuit. a rotatable member, manually operable means for turning said rotatable member a variable angular distance, and a commutator device under the control of said rotatable member for rotating said element with respect to said contacts whereby the direction of polarity of said rectifier is reversed with respect to said contacts a predetermined number of times dependent upon the extent of the angular displacement of said rotatable member.

5. A pulsing device for a telecommunication switching system comprising a uni-directional current conducting device, contacts for connecting said device in a signalling circuit, a first rotatable member, a second rotatable member, means for turning said first rotatable member a variable angular distance from a normal position against the tension of a, spring, means for coupling said first rotatable member to said second rotatable member during its return movement to said normal position, and a rotary commutator device controlled by the rotation 01 said second rotatable member for reversing the direction of polarity of said uni-directional current conducting device with respect to said contacts a predetermined number of times dependent upon the extent of the angular displacement of said first rotatable member.

6. A pulsing device according to claim 5 wherein means is provided for insuring that said commutator device always returns to a rest position in which said uni-directional current conducting device has a predetermined polarity with respect to said contacts.

7. A pulsing device for a telecommunication switching system comprising a rotatable finger hole disc, a rotatable ratchet wheel, spring means for returning said disc to a fixed normal position, a pawl for rotating said ratchet wheel during the return movement of said finger hole disc, a rectifier element mounted on a spindle to rotate in bearings, a pair of diametrically arranged brushes mounted on said rectifier element and electrically connected to the two electrodes thereof, a pair of substantially semi-circular segmental contacts adapted to be engaged by said brushes during the rotation of said rectifier element and a mechanical coupling between said ratchet wheel and said spindle.

8. A pulsing device according to claim 7 wherein alternate teeth of said ratchet wheel are of increased radial length and means is provided for adjusting the position of said pawl as the said finger hole disc approaches its position of rest so that said pawl always engages a long tooth when the said disc is in its rest position.

9. A pulsing device according to claim 7 further comprising a plurality of contact springs, a plate mounted to rotate with said finger disc and a pin mounted on said plate and arranged to actuate said contact springs when said finger disc is moved out of its position of rest.

10. A pulsing device for a telecommunication switching system comprising a rotatable finger hole disc, means for turning said disc a variable angular distance from its normal position against the tension of a spring, a rotatable member, means for coupling said disc to said member during the return movement of the disc to its normal position, a dry contact rectifier, contacts for connecting said rectifier in a signalling circuit and means actuated by said rotatable member on the return movement of said disc to reverse the direc tion of polarity of said rectifier with respect to said contacts a predetermined number of times dependent upon the angular displacement of said disc.

11. A pulsing device according to claim 1 in which said pair of contacts for connecting said element in a signalling circuit comprises a pair of essentially semicircular contacts.

GERALD DEAKIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITE]: STATES PATENTS Number Name Date 1,743,711 Field Jan. 14, 1930 2,052,057 Reid Aug. 25, 1936 2,136,630 Massonneau Nov. 15, 1938 2,259,334 Wright Oct. 14, 1941 316,686 Hoevenbergh Apr. 28, 1885 1,415,369 Lehman May 9, 1922 1,251,249 Lehman Dec. 25, 1917 

